37,046 results match your criteria Organic Solvents

Deep-eutectic solvents/ionic liquids/water mixture as a novel type of green thermo-switchable solvent system for selective extraction and separation of natural products from Rosmarinus officinalis leaves.

Food Chem 2022 May 16;390:133225. Epub 2022 May 16.

State Key Laboratory of Natural Medicines, China Pharmaceutical University, No. 24 Tongjia Xiang, Nanjing 210009, China. Electronic address:

In the present study, we designed a novel type of green thermo-switchable solvent system which is composed of ChCl:LA/[BMIM]PF/HO (v/v/v, 1/2/1) to extract natural products. When the temperature is 60 ℃, the system is a homogeneous single-phase system, and when cooling to 25 ℃, the system is switched into a heterogeneous two-phase system. Based on the thermo-switchable system, an integrated extraction method was developed which could efficiently extract both rosmarinic acid (hydrophilic) and carnosic acid (hydrophobic) from Rosmarinus officinalis leaves at 60 ℃ and in situ separate the extracted compounds with high recovery yields by cooling the extracts to 25 ℃. Read More

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Water-in-oil high internal phase Pickering emulsions formed by spontaneous interfacial hydrolysis of monomer oil.

J Colloid Interface Sci 2022 May 7;623:476-486. Epub 2022 May 7.

Department of Chemistry, The Chinese University of Hong Kong, Shatin, NT, Hong Kong. Electronic address:

Hypothesis: Alcohols can strongly reduce the interfacial tension between immiscible liquids, thus facilitating the formation of emulsions. By combining non-surface-active hydrophobic particles with medium-chain alcohols, stable water-in-oil (w/o) high internal phase Pickering emulsions (HIPPEs) can be easily prepared without high-energy emulsification methods.

Experiments: The emulsions containing acrylate monomer as the oil phase were prepared at different pH values in the presence of hydrophobic silica particles. Read More

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In-situ sorbent formation for the extraction of pesticides from honey.

J Sep Sci 2022 May 20. Epub 2022 May 20.

Food and Drug Safety Research, Tabriz University of Medical Sciences, Tabriz, Iran.

An organic polymer was re-precipitated in solution to use as an adsorbent in dispersive solid phase extraction of some pesticides from honey samples prior to their determination by high performance liquid chromatography-tandem mass spectrometry. In this approach, different deep eutectic solvents were prepared using lysine and their ability in elution of the analytes from the adsorbent surface were tested. A diluted honey solution was transferred into a glass test tube and then a solution of polystyrene dissolved in dimethylformamide was injected into the solution. Read More

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Sulfolane as Common Rate Accelerating Solvent for the Cationic Ring-Opening Polymerization of 2-Oxazolines.

ACS Macro Lett 2015 Aug 20;4(8):825-828. Epub 2015 Jul 20.

Supramolecular Chemistry Group, Department of Organic and Macromolecular Chemistry, Ghent University, Krijgslaan 281, S4, Ghent, Belgium.

The search for alternative solvents for the cationic ring-opening polymerization (CROP) of 2-methyl-2-oxazoline (MeOx) is driven by the poor solubility of P(MeOx) in polymerization solvents such as acetonitrile (CHCN) and chlorobenzene as well as in MeOx itself. In this study, solvent screening has revealed that especially sulfolane is a good solvent for PMeOx. Unexpectedly, an increased propagation rate constant () was found for the CROP of MeOx in sulfolane. Read More

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Chemically Driven, Water-Soluble Composites of Carbon Nanotubes and Silver Nanoparticles as Stretchable Conductors.

ACS Macro Lett 2015 Jul 6;4(7):769-773. Epub 2015 Jul 6.

Center for Emerging Electronic Devices and Systems, School of Materials Science and Engineering, Gwangju Institute of Science & Technology, 123 Cheomdangwagi-ro, Buk-gu, Gwangju 500-712, Republic of Korea.

In the past decade, hybrid materials for highly stretchable, conductive electrodes have received tremendous attention in the fields of emerging wearable electronic, optoelectronic, and sensing devices. Here, we present a previously unrecognized aqueous route to producing stretchable conductors composed of silver nanoparticles (AgNPs) and single-walled carbon nanotubes (SWNTs) embedded in a polyurethane (PU) matrix, in contrast to ones dispersed in toxic organic solvents reported to date. The intact chemical interaction between one-dimensional SWNTs, for endowing the capability of establishing conductive pathways even in stretching conditions, and AgNPs, for enabling high conductivity of the composites, is achieved in an aqueous medium with an anionic polyelectrolyte, poly(acrylic acid), that undergoes pH-dependent conformational evolution. Read More

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Noncovalent Functionalization of Graphene Nanosheets with Cluster-Cored Star Polymers and Their Reinforced Polymer Coating.

ACS Macro Lett 2015 Sep 25;4(9):974-978. Epub 2015 Aug 25.

State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun 130012, China.

A noncovalent and phase-transfer-assisted method is developed for the fabrication of polymer-functionalized graphene, in which a series of cluster-cored star polymers (CSPs) containing a polyoxometalate core and polystyrene (PS) arms are used as modifiers. Through the electron transfer interaction between polyoxometalate and graphene, the CSPs can strongly adsorb on graphene nanosheets and transfer them from aqueous media to organic solvents like chloroform, forming individually dispersed graphene. Moreover, the CSP-functionalized graphene is well compatible with additional polymer matrices and can serve as a reinforcing nanofiller for polymer composites. Read More

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September 2015

Living Vinyl Addition Polymerization of Substituted Norbornenes by a -BuP-Ligated Methylpalladium Complex.

ACS Macro Lett 2015 Mar 2;4(3):327-330. Epub 2015 Mar 2.

Department of Chemical and Biological Engineering, Princeton University, Princeton, New Jersey 08544, United States.

The vinyl addition polymerization of substituted norbornene (NB) monomers, via (-BuP)PdMeCl activated by [Li(OEt)]B(CF), is investigated. NB monomers bearing alkyl, aryl, fluoroaryl, and even hexafluoroisopropanol substituents yield polymers exhibiting monomodal and narrow molecular weight distributions, with molecular weight controlled by reaction time and monomer to initiator ratio, demonstrating the living nature of these polymerizations. These polymers are soluble in common organic solvents and possess excellent thermal stability. Read More

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In silico folding of hydrophobic peptides that form β-hairpin structures in solution.

J Pept Sci 2022 May 20:e3427. Epub 2022 May 20.

CSIR - Centre for Cellular and Molecular Biology, Hyderabad, India.

Peptides designed with residues that have a high propensity to occur in β-turns form β-hairpin structures in apolar as well as in polar organic solvents such as dimethyl sulfoxide (DMSO). Due to limited solubility, their conformations have not been investigated experimentally in water. We have examined the conformations of four of such designed peptides that fold into well-defined β-hairpin structures facilitated by β-turns, in the crystalline state and in solution, by molecular dynamics simulations (MDS). Read More

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Head-to-Tail Regioregular Polythiazole Prepared via Kumada-Coupling Polycondensation.

ACS Macro Lett 2014 Feb 22;3(2):170-174. Epub 2014 Jan 22.

Institut für Organische Chemie II und Neue Materialien, Universität Ulm, Albert Einstein Allee 11, 89081 Ulm, Germany.

Head-to-tail regioregular poly(4-alkylthiazoles) (, , alkyl = -CH, -CH) have been synthesized and spectroscopically and electrochemically characterized. The s were obtained by transmetalation of 2-chloro-5-bromo-4-alkylthiazoles with PrMgCl, followed by Kumada-coupling polycondensation. The polymers are largely insoluble in organic solvents but dissolve readily in the presence of, e. Read More

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February 2014

Complex Composites Built through Freezing.

Acc Chem Res 2022 May 19. Epub 2022 May 19.

Université de Lyon, INSA Lyon, Université Claude Bernard Lyon 1, CNRS, MATEIS UMR 5510, 69621 Villeurbanne, France.

ConspectusUsing a limited selection of ordinary components and at ambient temperature, nature has managed to produce a wide range of incredibly diverse materials with astonishingly elegant and complex architectures. Probably the most famous example is nacre, or mother-of-pearl, the inner lining of the shells of abalone and certain other mollusks. Nacre is 95% aragonite, a hard but brittle calcium carbonate mineral, that exhibits fracture toughness exceedingly greater than that of pure aragonite, when tested in the direction perpendicular to the platelets. Read More

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Extraction of Bioactive Compounds From L. Flowers and/or Leaves Using Deep Eutectic Solvents.

Front Nutr 2022 2;9:892314. Epub 2022 May 2.

LAQV/REQUIMTE, Chemistry Department, NOVA School of Science and Technology, Monte de Caparica, Portugal.

The increasing demand for medical cannabis urges the development of new and effective methods for the extraction of phytocannabinoids. Deep eutectic solvents (DESs) are an alternative to the use of hazardous organic solvents typically used in the industry. In this study, hydrophilic and hydrophobic DESs were developed based on terpenes, sugars, and natural organic acids as green extraction media for the extraction of cannabis bioactive compounds. Read More

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Site-Selective Silver-Catalyzed C-H Bond Deuteration of Five-Membered Aromatic Heterocycles and Pharmaceuticals.

ACS Catal 2021 Feb 10;11(3):1119-1127. Epub 2021 Jan 10.

Department of Chemistry, University of California, Berkeley, California 94720, United States.

Catalytic methods for the direct introduction of hydrogen isotopes into organic molecules are essential to the development of improved pharmaceuticals and to the alteration of their absorption, distribution, metabolism, and excretion (ADME) properties. However, the development of homogeneous catalysts for selective incorporation of isotopes in the absence of directing groups under practical conditions remains a long-standing challenge. Here, we show that a phosphine-ligated, silver-carbonate complex catalyzes the site-selective deuteration of C-H bonds in five-membered aromatic heterocycles and active pharmaceutical ingredients that have been resistant to catalytic H/D exchange. Read More

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February 2021

Recent Advances in Polysaccharide-Based Physical Hydrogels and Their Potential Applications for Biomedical and Wastewater Treatment.

Macromol Biosci 2022 May 18:e2200153. Epub 2022 May 18.

Institute of Chemical Industry of Forest Products, CAF, Key Lab. of Biomass Energy and Material, Jiangsu Province, National Engineering Research Center of Low-Carbon Processing and Utilization of Forest Biomass, Key Lab. of Chemical Engineering of Forest Products, National Forestry and Grassland Administration, Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, Nanjing, 210042, China.

Polysaccharides have been widely employed to fabricate hydrogels owing to their intrinsic properties including biocompatibility, biodegradability, sustainability, and easy modification. However, a considerable amount of polysaccharide-based hydrogels are prepared by chemical crosslinking method using organic solvents or toxic crosslinkers. The presence of reaction by-products and residual toxic substances in the obtained materials cause a potential secondary pollution risk and thus severely limited their practical applications. Read More

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Online microdroplet calibration for accurate nanoparticle quantification in organic matrices.

Anal Bioanal Chem 2022 May 18. Epub 2022 May 18.

Department of Chemistry, Iowa State University, Ames, IA, 50010, USA.

Single-particle inductively coupled plasma time-of-flight mass spectrometry (spICP-TOFMS) is a high-throughput method for the multiplexed analysis of nanoparticles (NPs). However, matrix interferences are a significant challenge that must be overcome for accurate NP sizing and number concentration determination. In online microdroplet calibration, multi-element droplet standards are mixed with nebulized aerosols from a NP-containing sample in a dual-sample introduction system before entering the ICP. Read More

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Time-Dependent Hydrogen Bond Network Formation in Glycerol-Based Deep Eutectic Solvents.

Chemphyschem 2022 May;23(10):e202200283

CERN, Esplanade des Particules 1, 1211, Geneva, Switzerland.

The front cover artwork is provided by Patryk Palenque Marcinkowski. The image shows a glycerol-choline network accommodating water molecules over time. The glycerol molecules are represented as pandas adapting to the change. Read More

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Perspectives of nano-carrier drug delivery systems to overcome cancer drug resistance in the clinics.

Cancer Drug Resist 2021 19;4(1):44-68. Epub 2021 Mar 19.

Drug Delivery and Targeting Group, Molecular Biology and Biochemistry Research Centre for Nanomedicine (CIBBIM-Nanomedicine), Vall d'Hebron Institut de Recerca, Universitat Autònoma de Barcelona, Barcelona 08035, Spain.

Advanced cancer is still considered an incurable disease because of its metastatic spread to distal organs and progressive gain of chemoresistance. Even though considerable treatment progress and more effective therapies have been achieved over the past years, recurrence in the long-term and undesired side effects are still the main drawbacks of current clinical protocols. Moreover, a majority of chemotherapeutic drugs are highly hydrophobic and need to be diluted in organic solvents, which cause high toxicity, in order to reach effective therapeutic dose. Read More

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Iridescent Chiral Nematic Cellulose Nanocrystal/Polymer Composites Assembled in Organic Solvents.

ACS Macro Lett 2013 Nov 1;2(11):1016-1020. Epub 2013 Nov 1.

Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, British Columbia V6T 1Z1, Canada.

We describe an approach to prepare polymer composites with chiral nematic photonic structures through the self-assembly of cellulose nanocrystal (CNC) dispersions in organic solvents. Contrary to previous reports, we demonstrate that dispersions of neutralized sulfated CNCs in polar organic media readily form lyotropic chiral nematic liquid crystalline phases. We have investigated the effect of the neutralizing base on the CNC self-assembly, observing chiral nematic ordering for all counterions studied. Read More

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November 2013

Ring-Opening Metathesis Polymerization by a Ru Phosphine Derivative of Cyclodextrin in Water.

ACS Macro Lett 2013 May 22;2(5):384-387. Epub 2013 Apr 22.

Department of Macromolecular Science, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan.

Trimethylated cyclodextrins with a phosphine ligand and ruthenium (PCyRu-CDs) realize supramolecular polymerization catalysts for ring-opening metathesis polymerization (ROMP). Although PCyRu-βCD shows a low polymerization activity for 7-oxanorbornene dimethanol (7-ONorOH) in organic solvents, it exhibits a high ROMP activity for 7-ONorOH in aqueous solutions. The ROMP activity of PCyRu-βCD is higher than that of PCyRu-αCD. Read More

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Robust Microsieves with Excellent Solvent Resistance: Cross-Linkage of Perforated Polymer Films with Honeycomb Structure.

ACS Macro Lett 2013 Jan 20;2(1):27-30. Epub 2012 Dec 20.

College of Materials, Xiamen University, Xiamen, 361005, People's Republic of China.

Polymeric microsieves with uniform and tunable pores were fabricated with the breath-figure method and sequent vulcanization procedure using commercially available block copolymer polystyrene--polyisoprene--polystyrene. Uniform pore size and small film thickness endow the microsieves with high size selectivity and low operation pressure, while the cross-linked chemical structure gives them good mechanical properties and excellent chemical and thermal stability. These microsieves are able to separate particles in various media, including corrosive solvents, hot water, and organic solvents. Read More

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January 2013

The p Hydrogen-Bond Basicity Scale: From Molecules to Anions.

J Org Chem 2022 May 17. Epub 2022 May 17.

Nantes Université, CNRS, CEISAM, UMR 6230, F-44000 Nantes, France.

The p (logarithm of complexation constant of 4-fluorophenol with bases) hydrogen-bond basicity scale of neutral hydrogen-bond acceptors (HBAs) is extended to anionic HBAs. The scale is constructed for 26 anions through (i) the infrared measurement of on NBuX ion pairs in CCl, (ii) the estimation of from linear free energy relationships between measured values and literature values for various phenols in polar solvents, and (iii) the computation of at the density functional theory level in CCl. The scale extends on a 9. Read More

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Fast and eco-friendly method using atmospheric solids analysis probe mass spectrometry to characterize orange varieties.

J Mass Spectrom 2022 Jun;57(6):e4828

Department of Chemistry, State University of Maringá (UEM), Maringá, Brazil.

Orange fruit is one of the most popular types of fruit in the world, and its juice is the main product of its processing. This study aimed to evaluate a simple, fast, and eco-friendly methodology, atmospheric solids analysis probe mass spectrometry (ASAP-MS), to assess the chemical profile of four oranges varieties (Valencia, Folha Murcha, Pera, and Iapar). The oranges' varieties were evaluated for the physicochemical composition (extraction yield, pH, total titratable acidity, total soluble solids [TSS], °Brix), ratio (TSS/TA), and bioactive compounds (ASAP-MS analysis). Read More

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Synthesis and Properties of Polymers Containing 2-Benzimidazol-2-one Moieties: Polymerization via N-C Coupling Reactions.

ACS Macro Lett 2012 Jan 14;1(1):194-197. Epub 2011 Dec 14.

Department of Chemistry, McGill University, Montreal, Quebec H3A2K6, Canada.

Novel homopolymers and copolymers containing 2-benzimidazol-2-one units have been synthesized by N-C coupling reactions of 1-benzo[]imidazol-2(3)-one and activated aromatic dihalides under conditions similar to those for the synthesis of poly(aryl ether)s and poly(benzimidazole sulfone)s. 1-Benzo[]imidazol-2(3)-one behaved like a bisphenol in the polymerization reaction to afford, quantitatively, high molecular weight linear polymers with inherent viscosities (η) ranging from 0.57 to 1. Read More

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January 2012

Maternal occupational exposure to chemicals and child cognitive function.

Pediatr Res 2022 May 16. Epub 2022 May 16.

Department of Medicine, Baylor College of Medicine, Houston, TX, USA.

Background: Limited data exist regarding child neurodevelopment in relation to maternal occupational exposure to endocrine-disrupting chemicals (EDCs).

Methods: We included 1058 mother-child pairs from the INfancia y Medio Ambiente (INMA) project (2003-2008). Using a job-exposure matrix, exposure probability scores for ten EDC groups were assigned to each mother based on her longest held job during pregnancy. Read More

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Volatile organic compounds emission in the rubber products manufacturing processes.

Environ Res 2022 May 13;212(Pt C):113485. Epub 2022 May 13.

Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; University of Chinese Academy of Sciences, Beijing, 100049, China.

Volatile organic compounds (VOCs) emission from rubber products manufacture processes, mixing, shaping and vulcanization were investigated in four rubber products factories in China. The source emission air was passively sampled by pre-vacuumized stainless steel canister and analyzed by gas chromatography-mass spectrometry-flame ionization detection (GC/MS-FID). The species profile of 107 VOCs in the emission processes were obtained. Read More

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Determination of amoxicillin trihydrate impurities 4-HPG and 6-APA by means of ultraviolet spectroscopy.

Methods Appl Fluoresc 2022 May 16. Epub 2022 May 16.

Department of Chemistry, Istanbul University-Cerrahpasa, İstanbul University-Cerrahpaşa, Department of Chemistry, Avcilar, Istanbul, Istanbul, 34320, TURKEY.

Amoxicillin is one of the broad-spectrum β-lactam antibiotics widely used in the treatment of many diseases. It is inevitable that 4-hydroxyphenylglycine (4-HPG) and 6-Aminopenicylanic acid (6-APA), which are used during the production of this antibiotic, are incorporated into the molecular lattice of the product as impurities. Today, many expensive methods and chemical devices are used for the purification of Amoxicillin by determining 6-APA and 4-HPG, which are defined as impurities. Read More

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Influence of solvents on the morphology of Langmuir and Langmuir-Schaefer films of PCBM and PCBM-based oligomers and polymers.

Phys Chem Chem Phys 2022 May 16. Epub 2022 May 16.

CNRS/Univ Pau & Pays Adour, Institut des Science Analytiques et Physico-Chimie pour l'Environnement et les Materiaux, Pau, France.

Fullerene-based polymers and oligomers combined with non-fullerene acceptors show extremely high efficiencies in organic photovoltaic devices. Furthermore, fullerene-based materials are of interest for use in anti-cancer and anti-viral treatments, where their presence can enhance the efficacy of medication considerably. Therefore, it remains important to understand their morphology and electronic properties to improve devices and technological applications. Read More

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Facile Synthesis of Solubilizing a Group-Free, Solution-Processable -Type Ladder Conjugated Polymer and Its Thermoelectric Properties.

ACS Macro Lett 2022 Jan 28;11(1):110-115. Epub 2021 Dec 28.

Agency of Science, Technology and Research (A*STAR), Institute of Materials Research and Engineering (IMRE), 2 Fusionopolis Way, Innovis, Singapore 138634, Singapore.

Here we report the synthesis of a new solubilizing group-free, solution-processable -type ladder conjugated polymer, 6-pyrrolo[3,2-:4,5-']bis[1,4]benzothiazine ladder (PBBTL) polymer by using a polyphosphoric acid (PPA) and phenylphosphonic acid (PhPOH) 1:1 binary acid solvent system together with careful control of reaction kinetics. With a good intrinsic viscosity of 3.69 dL/g in methanesulfonic acid (MSA), good quality PBBTL films can be obtained via spin-coating. Read More

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January 2022

Long-chain alkanol-alkyl carboxylic acid-based low-viscosity hydrophobic deep eutectic solvents for one-pot extraction of anthraquinones from Rhei Radix et Rhizoma.

J Pharm Anal 2022 Feb 17;12(1):87-95. Epub 2021 Mar 17.

Key Laboratory of Combinatorial Biosynthesis and Drug Discovery (Ministry of Education); Wuhan University School of Pharmaceutical Sciences, Wuhan, 430071, China.

Natural long-chain alkanol and alkyl carboxylic acid were used to prepare novel hydrophobic deep eutectic solvents (HDESs). These HDESs are liquid at room temperature and have low viscosity (<12.26 mPa‧s), low polarity (lower than that of methanol, ChCl-based deep eutectic solvents and other reported HDESs), and low density (<0. Read More

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February 2022

Characterization of the Interfacial Liquid Layer Formed on Hydrophobic Packing Material Surfaces by Liquid Chromatographic Analysis of the Distribution of Ions and Molecules.

ACS Omega 2022 May 19;7(17):15158-15166. Epub 2022 Apr 19.

Graduate School of Science and Technology, Saitama University, 255 Shimo-Okubo, Sakura-ku, Saitama 338-8570, Japan.

We determine the bulk liquid phase volumes in octadecyl-bonded silica (C silica) columns equilibrated with acetonitrile-water and methanol-water (0-19%(v/v)) binary mixed solvents by a liquid chromatographic method with inorganic ions used as probes. The solvent composition and the thickness of the interfacial liquid layer formed on the C-bonded silica surface are then determined from the bulk liquid phase volume, the total liquid phase volume, the surface area of the C silica packing material, and the retention volumes of the isotopically labeled eluent components for the columns. We used two C silica packing materials having identical bonding structures but different pore sizes and surface areas. Read More

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Toward Sustainable Solid Polymer Electrolytes for Lithium-Ion Batteries.

ACS Omega 2022 May 20;7(17):14457-14464. Epub 2022 Apr 20.

BCMaterials, Basque Center for Materials, Applications and Nanostructures, UPV/EHU Science Park, 48940 Leioa, Spain.

Lithium-ion batteries (LIBs) are the most widely used energy storage system because of their high energy density and power, robustness, and reversibility, but they typically include an electrolyte solution composed of flammable organic solvents, leading to safety risks and reliability concerns for high-energy-density batteries. A step forward in Li-ion technology is the development of solid-state batteries suitable in terms of energy density and safety for the next generation of smart, safe, and high-performance batteries. Solid-state batteries can be developed on the basis of a solid polymer electrolyte (SPE) that may rely on natural polymers in order to replace synthetic ones, thereby taking into account environmental concerns. Read More

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